Hey Andy, We also have a FAQ wiki page at http://wiki.apache.org/hadoop/FAQ you can send these kind of things to. Let me know your Apache Hadoop Wiki user-ID (you can sign up there), and we'll grant you edit rights.
On Tue, Nov 6, 2012 at 8:06 PM, Kartashov, Andy <andy.kartas...@mpac.ca> wrote: > Hello, > > Whenever you are getting below error, trying to start a DN on a slave machine: > java.io.IOException: Incompatible clusterIDs in /home/hadoop/dfs/data: > namenode clusterID = ****; datanode clusterID = **** > > It is because after you set up your cluster, you, for whatever reason, > decided to reformat your NN. Your DNs on slaves still bear reference to the > old NN. To resolve this simply delete and recreate data folder on that > machine in local Linux FS, namely /home/hadoop/dfs/data. Restarting that DN's > daemon on that machine will recreate data/ folder's content and resolve the > problem. > > Happy Hadooping, > AK47 > > NOTICE: This e-mail message and any attachments are confidential, subject to > copyright and may be privileged. Any unauthorized use, copying or disclosure > is prohibited. If you are not the intended recipient, please delete and > contact the sender immediately. Please consider the environment before > printing this e-mail. AVIS : le présent courriel et toute pièce jointe qui > l'accompagne sont confidentiels, protégés par le droit d'auteur et peuvent > être couverts par le secret professionnel. Toute utilisation, copie ou > divulgation non autorisée est interdite. Si vous n'êtes pas le destinataire > prévu de ce courriel, supprimez-le et contactez immédiatement l'expéditeur. > Veuillez penser à l'environnement avant d'imprimer le présent courriel -- Harsh J
